On the Facebook HHVM blog they talk about an improvement they've made to the project allowing for faster GitHub commits on the project. They've reworked things to move away from a manual process on the popular project and automate as much as possible.

Initially, the entire process was manual. We would curl the pull request and pipe it to git am, then manually prepare the diff for review internally. After it was accepted, we would manually prepare the internal commit to be usable externally by GitHub, then manually build and test the new code, and finally git push. Great scripts by ptarjan and sgolemon to help get and prepare pull requests for review and then prepare the commits for GitHub have alleviated some of this manual process. However, in the end, someone still had to manually build, test and then push the code to the world.

Another feature of this effort is a new cron job (facebook-github-bot) that pushes any internal (approved) HHVM code automatically without having to wait for the manual intervention. It syncs all code since the last push, runs all tests and, assuming all went well, pushes it out to GitHub.

we believe that getting your code into the master branch quickly will hopefully help show how much we appreciate your contributions. Now, if there was only a way we could get your pull requests reviewed faster and more openly…. Hmmm…